DISTRIBUTED RAINFALL-RUNOFF AND 2D FLOOD FLOWS ANALYSIS WITH PLURAL TRIBUTARIES IN THE ONGA RIVER BASIN

Abstract

The numerical simulations of rainfall-runoff and flood flows in the Onga river basin were performed. The rain-fall runoffs were simulated by a distributed hydrological model. The flood flows in the main river and plural tributaries were simulated simultaneously by the 2D unsteady free-surface flow model. The flooding event in the Onga river basin in July 2003, June 2004 and September 2004 were simulated by the model. The simulated results compared with the observed water level and discharge rating curve. It shows that the model is a useful tool for examining the process of runoff and flooding in the Onga river basin.